For the system shown in the figure, s = –2.75 lies on the root locus if K is_____.

Consider the Bode plot shown in the figure. Assume that all the poles and zeroes are real-valued. The value of f_H - f_L (in Hz) is ______.

The phase margin (in degrees) of the system G(s)=$${{10} \over {\left( {s + 10} \right)}}$$ is ___________.

The transfer function of a first-order controller is given as $${G_c}(s) = {{K\left( {s + a} \right)} \over {s + b}}$$

where k, a and b are positive real numbers. The condition for this controller to act as a phase lead compensator is